Resistance-terminal.



F. D. HALLOCK.

RESISTANCE TERMINAL.

APPLICATION mum JAN.3. 1906.

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INV ENTOR d m W WITNESSES: V 61. WW

ATTORNEY P. D. HALLOOK.

RESISTANCE TERMINAL.

APPLICATION FILED 5mm. 190a.

Patented J an. 18, 1910.

2 SHEETS-SHEET 2.

' AT'TORNEY 'ELE'rcHEB D. HALLOCK, or wrnxmsnuae, PENNSYLVANIA, assrcnoarow srIne- HOUSE ELECTRIC 8: MANUFACTURING COMPANY, A CORPORATION OFPENNSYL- VANIA.

RESISTANCE-TERMINAL.

Specification of Letters Patent.

Application filed January 3, 1906. Serial No. 294,468.

To'all it may concern:

Be it known that I, FLETCHER D. HAL- vIJocK",,-a citizen of the UnitedStates, and a resident'of \Vilkinsburg, in the county of Allegheny andState of Pennsylvania, have invented a new and useful Improvement inResistance-Terminals, of'which the following is a specification.

'My invention relates to terminals, con-. nectors or similar parts forelectrical apparatus and has special reference to con-- metal resistanceunits.

nectors which are adapted for use with cast The object oflm inventionis'to provide means for connecting'the several units of a cast metalresistance group that" shall be simple and durable in construction andshall have no appreciable resistance drop 'when' the connection iscompleted or after an indefinite lapse of time. p

The use of cast metal resistance units has become well known'in theprior art, and in .assemblingsuch resistance groups, connectors ofvarious kinds have been employed for completing the circuit from oneunit to another. Of. all the methods which have been employed forconnecting difl'e'rent units, perhaps the best results. have beenobtained by finishin a small surface on each resistance unit andfastening a strip of conducting material in engagement with this.

surface by binding screws. According to another well known method, theengaging surfaces of adjacent units which are to be connected arefinished and relatively heavy pressure applied to the assembled group inorder to keep the finished surfaces in close engagement with each other.It will be observed that in both of the methods ohtlin'ed representativeof prior practice, acertain amount of machining is essential andfurthermore, although a slight resistance drop may be detected when theresistance group is first assembled, this drop has been found toincrease, after the resistance has been in service for a considerablelength of-time, to such an extent that the total ohmic resistance of thegroup is substantially increased by reason of the oxidation of thecontact surfaces. This is particularly true of resistances which aresubjected to severe weather conditions, such'as street railwaydiverters.

' l per, is cast into the extremities of each resistance unit and theprojecting portions are divided longitudinally into two similar parts bya slot or sawcut. In 'thisway, the cast units may be assembled withoutmachining and the connectors of ad acent units, which are to beelectrically connected, are riveted Patented Jan. 18. 1910 tainedbetween surfaces of a conducting section, of a resistance group of thegrid type having the connectors of myinvention,

and Fig. 2 is an end elevation of the resistance of group of Fig. 1.Fig. 3 is a sectional elevation of a modified form of resistance 'unitwith which lily-improved connector may advantageously be employed.

Referring to Figs. 1 and 2, the reslstancc group illustrated thereincomprisesa plu- -rality of similar cast. metal resistance units 1mounted upon a plurality of insulated rods 2, 3 and 4, which constitute,together structure which is supported at three points and which isstiffened by widening the strip at and near the points of connection tothe rods 2, 3 and 4. The several units are insulated from the endcastings by insulating and spacing Washers (i and are insulated fromeach other at suitable points by'rela tively thin washers 7elf-insulating mate" rial, such as mica. The extremities of each unitadjacent to the rods 2 and t are provided with strips 8, of conductingmaterial which are cast into the unitand' may serve as supports forterminals 9 or as connectors. The portion of each strip-8 which projectsfrom the casting is divided longitudinally into two portions by a sawcutor slot 10 so that one'portion may be bent. in one direction and theother portion in the opposite direction in case it is de sired toconnect any one unit with the adwith a pair of end castingsfi, asupporting .a multiple circuit arrangement. several units are to beconnected in series relation the connectors on corresponding jacentunits at each side in order to rovide W ien the of high resistancematerial such as metallic silicon provided with connectors 8 similar tothe strips Sof Figs; 1 and 2 which are cast into the unit near itsextremities. Several units of this form may be used either by themselvesor in'ooinbination with units like those set forthein latentaNo.788,686, grant ed to the Vestinghouse Electric & Manufacturing Company,as assignee of Hermon L. Van Valkenburg, or other units of the same"eneral form and dimensions.

Alt rough I have illustrated the connector of my invention as applied tospecific types of resistance units, its use is not re stricted theretoand it is to be understood that considerable variations in the size andshape of the terminal members may be effected within the scope of myinvention.

I claim as my invention:

1. A cast metal resistance unit havingflexible terminal or connectingstrips of conducting material cast into and projectmg from tsextremities, the outer portions ofsaid strips being divided bylongitudinal slots intotwo substantially similar ears.

2. A resistance unit comprising a casting having two branches of zigzagformation the outer extremltles of whlch and the unction between whlehare enlarged and provide'd with holes to receive insulated rods andhavin terminal or connecting members of relative y low resistanceconduct n material castinto the extremities 'o the branches and providedwithho'les through subscribed my name this 30th day of December 1905.

FLETCHER DnHALLoeKQ v Witnesses .3

an R. J. Deana ax, Bmxnr Hixns.

